NEW YORK -- Baseball's long wait for a World Cup-style international tournament, with the game's best players representing their countries, is over.

Major League Baseball and the Major League Baseball Players Association jointly announced Wednesday that the "World Baseball Classic," a 16-nation tournament featuring the world's best players competing for their home countries, will be played in March 2006.

"This gathering of baseball's brightest stars will be an outstanding platform to grow the game internationally," commissioner Bud Selig said. "As baseball continues to grow globally, more and more fans around the world have the opportunity to appreciate the grace and excitement of our great game. The first World Baseball Classic will bring a unique blend of enthusiasm to old and new fans alike."

The tournament will be staged across three weeks next March and will be the first full-scale event involving major-league players representing their home countries. Olympic tournaments included only amateur players from 1984-96, after which professionals have been eligible. Because of scheduling conflicts, however, international competition has generally involved minor-leaguers.

Though player participation will be voluntary, the prospect of having stars-and-stripes-clad Roger Clemens facing Albert Pujols and Vladimir Guerrero of the Dominican Republic, with flags waving throughout the stands, has long intrigued baseball officials, players and fans.

"I would like to play in that, but the Dominican has a lot of good players," Mariners third baseman Adrian Beltre said last year. "Who knows if I would be in it? If I was [chosen] to be in it, I'd like to represent my country."

According to one union official, MLB and the MLBPA will jointly run the tournament through an MLB subsidiary called World Baseball Classic Inc., which will include representatives of MLB, the union and the International Baseball Federation (IBAF), which is the governing body for international baseball. Neither official would discuss details of how money from sponsorships, television rights and the like will be distributed.

Much of the tournament structure has been decided, subject to minor modifications.

"The World Baseball Classic reflects and will demonstrate the continued growth of baseball's appeal worldwide," said MLBPA executive director Donald Fehr. "We thank the participating leagues, players associations and federations for agreeing to be a part of this event. Major Leaguers look forward to the World Baseball Classic with great anticipation."

Organizers are in the process of formally inviting 16 nations, with the only question mark being Cuba, whose invitation must be cleared by the U.S. State Department and then subject to approval by Fidel Castro. The teams will start play in four four-team pools that will play round-robins in different countries.

Japan, Korea, Taiwan and China will play March 3-5, probably at Japan's Tokyo Dome. The three other pools will play March 8-11 and consist of: Puerto Rico, Cuba (for now), Panama and likely Italy; the United States, Canada, Mexico and likely South Africa; and the Dominican Republic, Venezuela, Australia and the Netherlands. The first pool will play in Puerto Rico, perhaps at Hiram Bithorn Stadium, while the other two would play at Arizona and Florida spring training sites to be determined.

The two teams in each pool with the best records would advance to the second round, another round-robin, on March 13-15 at different major-league stadiums. Houston's Minute Maid Park, Los Angeles' Dodger Stadium and San Diego's Petco Park have long been considered strong candidates.

The four outright winners of those pools would each advance to a single-game semifinal on March 18, again at a major-league stadium. The winners of those games will meet for a winner-take-all final March 20 -- a Monday, presumably to avoid television conflicts with the NCAA men's basketball tournament.

Team rosters, currently set at 27 players, will be chosen according to Olympic eligibility guidelines by tournament organizers. According to one union official, major-league clubs will not be able to block any of their players from participating. Several teams, most vocally the Yankees, have expressed concerns both privately and publicly about their high-priced stars possibly getting injured before the season starts. The Yankees have also been reluctant to release their minor-leaguers for USA Baseball's teams in 1999, 2000, 2001 and 2003.

"What is [George] Steinbrenner going to say if he loses a $20 million player?" current Yankees slugger Gary Sheffield told The New York Times last year. "How is that going to sit with him?"

One union official said that insurance to cover player contracts in the event of injuries during the tournament had been addressed to MLB's satisfaction.

Special guidelines, to be determined by a tournament committee, will limit how pitchers can be used, probably with rules on specific pitch limits and required rest for both starters and relievers. This is to placate both clubs and insurance companies -- as one union official said last year, "We don't want [Angels closer] Frankie Rodriguez, out of national pride, to pitch two innings [for Venezuela] three days in a row."

MLB and the union have talked about joining forces for a tournament of this sort since the early 1990s but only in the past several years have worked hard to make it happen. One year ago there were expectations of a tournament to be held this past March, but several complicating factors -- particularly securing sanction from IBAF, which came this March -- delayed its final formulation until now.

Negotiation of an agreement regarding drug testing also contributed to the long tournament negotiations. Last year, players and owners agreed to a policy consistent with the guidelines set by the World Anti-Doping Agency and the Olympic movement, which are generally considered stronger than the ones currently governing all major-league players and the subject of considerable debate.